The present invention generally relates to avionics, and more particularly relates to weather radars, and even more particularly relates to methods and systems for enhanced turbulence detection.
Over the years, the tasks and results expected of a commercial airline pilot have increased. The cockpit of a typical modern commercial jetliner is much more elaborate with electronic navigation, communication, and control equipment, than that of an early commercial passenger aircraft. This equipment, in general, has proven to be quite beneficial. A prime example is the weather radar, which, among other things, is extremely helpful in detecting turbulence. However, these weather radar based turbulence detectors, which often use the existence of large standard deviations of wind velocities to indicate turbulence, have been plagued with the persistent problems of alerting the pilot to high turbulence levels when, in fact, the level of turbulence is relatively low.
To address these problems, typically, a pilot might adjust the threshold for alerting turbulence upward to reduce the number of false alarms.
While this attempt at reducing false alerts of turbulence has been used extensively in the past, it does have some drawbacks.
The primary drawback is that while raising the alert threshold does reduce the overall number of false alarms, it also reduces the number of legitimate and desired alarms as well. The pilot then has reduced ability to avoid relatively light to moderate turbulence.
Consequently, there exists a need for improved methods and systems for enhancing turbulence detection and alerting by airborne weather radars.
It is an object of the present invention to provide a system and method for enhancing the turbulence detection capability while suppressing the false alarm rate.
It is a feature of the present invention to remove from consideration by turbulence detection processes, portions of the detected radar returns which relate to vertical shear components of wind velocities.
It is a feature of the present invention to utilize a plurality of different geometrically oriented antenna scans.
It is another feature of the present invention to include a comparison of airborne measured average wind velocities gradients as a function of beam geometry and orientation (i.e. elevation), with known wind velocity gradients as a function of elevation, which known gradients have associated with them known vertical shear components.
It is an advantage of the present invention to achieve improved efficacy of turbulence detection using airborne weather radars.
The present invention is an apparatus and method for improving the quality of turbulence detection and alerting in avionics weather radars, which is designed to satisfy the aforementioned needs, provide the previously stated objects, include the above-listed features, and achieve the already articulated advantages. The present invention is carried out in a xe2x80x9cmis-identification-lessxe2x80x9d manner in a sense that the mis-identification of vertical wind shear as turbulence has been greatly reduced. The present invention is also carried out in a xe2x80x9chigh alert threshold-lessxe2x80x9d manner in the sense that pilot alert threshold increases and their concomitant elimination of legitimate relatively low and moderate level turbulence alerts have been reduced.
Accordingly, the present invention is a system and method including multiple differently angled, weather radar scans and a computer comparison of average wind velocity elevation gradients from radar returns in relation to known average wind velocity elevation gradients having known vertical speed components.